Cenozoic Era, the most recent great division of geological time, including the present. It follows the Mesozoic (middle-life) Era. The Cenozoic Era is divided by most geologists into the Tertiary and Quaternary periods. Geologists estimate that the Cenozoic Era began some 65,000,000 years ago.Cenozoic Era animals date from 65 million years ago to the present.
At best, fossilization is a long and tricky process that mineralizes an occasional Tyrannosaurus rex or other extraordinary find. How has that affected our chances at charting a model of life itself?
When it comes to fossils, specimens like Sue the Tyrannosaurus rex grab much of the attention. And while Sue is a staggering 67 million years old, she's a new kid on the block, compared to some of the oldest fossils ever found. What's older than Sue?